Subject: Gaussian, Electron Density and AIM

From: "Phil Hultin" <[email-masked]>
Date: Mon, 4 Mar 2002 11:17:49 -0600

Dave Shobe wrote:

>Come to think of it, I vaguely remember some kind of function, related to
>AIM analysis (atoms-in-molecues, based on the eletcron density
distribution)
>that had a maximum in lone pair regions of a molecule.

Dave is referring to the Laplacian of the electron density, which can be
interpreted in terms of electron pair densities.  The short introduction to
AIM by Paul Popelier (a paperback book, roughly 150 pages as I recall)
discusses this idea in some detail.

I am not a disciple or anything, but if one is trying to dissect the charge
distribution in a molecule, it appears to me that AIM is probably the best
way to do it.  At least, it has the virtue of being based on mathematically
rigorous analysis of the calculated or observed electron density.  It does
not impose any pre-conceptions on how charge is assigned to atoms.

Dr. Philip G. Hultin
Associate Department Head and
Associate Professor of Chemistry
University of Manitoba
Winnipeg, MB, Canada R3T 2N2
(vox) 204-474-9814
(fax) 204-474-7608
mailto:[email-masked]
http://www.umanitoba.ca/chemistry/

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From: "Alexandre Hocquet" <[email-masked]>
Date: Tue, 5 Mar 2002 01:59:34 +0100

It is also described in this paper :
"On the Full Topology of the Laplacian of the Electron Density.", P.L.A.
Popelier, Coord. Chem. Rev., 197, 169-189 (2000).
with the example of the H2O molecule.
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Alexandre HOCQUET
Laboratoire de Physicochimie Biomoléculaire et Cellulaire
ESA CNRS 7033
[email-masked]
Fax: 33 1 44277560
LPBC, case courrier 138
4 Place Jussieu, 75252 PARIS Cedex 05 France
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